08 Dec, 2013
1 commit
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[ Upstream commit 51c37a70aaa3f95773af560e6db3073520513912 ]
For properly initialising the Tausworthe generator [1], we have
a strict seeding requirement, that is, s1 > 1, s2 > 7, s3 > 15.Commit 697f8d0348 ("random32: seeding improvement") introduced
a __seed() function that imposes boundary checks proposed by the
errata paper [2] to properly ensure above conditions.However, we're off by one, as the function is implemented as:
"return (x < m) ? x + m : x;", and called with __seed(X, 1),
__seed(X, 7), __seed(X, 15). Thus, an unwanted seed of 1, 7, 15
would be possible, whereas the lower boundary should actually
be of at least 2, 8, 16, just as GSL does. Fix this, as otherwise
an initialization with an unwanted seed could have the effect
that Tausworthe's PRNG properties cannot not be ensured.Note that this PRNG is *not* used for cryptography in the kernel.
[1] http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme.ps
[2] http://www.iro.umontreal.ca/~lecuyer/myftp/papers/tausme2.psJoint work with Hannes Frederic Sowa.
Fixes: 697f8d0348a6 ("random32: seeding improvement")
Cc: Stephen Hemminger
Cc: Florian Weimer
Cc: Theodore Ts'o
Signed-off-by: Daniel Borkmann
Signed-off-by: Hannes Frederic Sowa
Signed-off-by: David S. Miller
Signed-off-by: Greg Kroah-Hartman
05 Dec, 2013
1 commit
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commit 312b4e226951f707e120b95b118cbc14f3d162b2 upstream.
Some setuid binaries will allow reading of files which have read
permission by the real user id. This is problematic with files which
use %pK because the file access permission is checked at open() time,
but the kptr_restrict setting is checked at read() time. If a setuid
binary opens a %pK file as an unprivileged user, and then elevates
permissions before reading the file, then kernel pointer values may be
leaked.This happens for example with the setuid pppd application on Ubuntu 12.04:
$ head -1 /proc/kallsyms
00000000 T startup_32$ pppd file /proc/kallsyms
pppd: In file /proc/kallsyms: unrecognized option 'c1000000'This will only leak the pointer value from the first line, but other
setuid binaries may leak more information.Fix this by adding a check that in addition to the current process having
CAP_SYSLOG, that effective user and group ids are equal to the real ids.
If a setuid binary reads the contents of a file which uses %pK then the
pointer values will be printed as NULL if the real user is unprivileged.Update the sysctl documentation to reflect the changes, and also correct
the documentation to state the kptr_restrict=0 is the default.This is a only temporary solution to the issue. The correct solution is
to do the permission check at open() time on files, and to replace %pK
with a function which checks the open() time permission. %pK uses in
printk should be removed since no sane permission check can be done, and
instead protected by using dmesg_restrict.Signed-off-by: Ryan Mallon
Cc: Kees Cook
Cc: Alexander Viro
Cc: Joe Perches
Cc: "Eric W. Biederman"
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
Signed-off-by: Greg Kroah-Hartman
01 Nov, 2013
1 commit
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Commit b1adaf65ba03 ("[SCSI] block: add sg buffer copy helper
functions") introduces two sg buffer copy helpers, and calls
flush_kernel_dcache_page() on pages in SG list after these pages are
written to.Unfortunately, the commit may introduce a potential bug:
- Before sending some SCSI commands, kmalloc() buffer may be passed to
block layper, so flush_kernel_dcache_page() can see a slab page
finally- According to cachetlb.txt, flush_kernel_dcache_page() is only called
on "a user page", which surely can't be a slab page.- ARCH's implementation of flush_kernel_dcache_page() may use page
mapping information to do optimization so page_mapping() will see the
slab page, then VM_BUG_ON() is triggered.Aaro Koskinen reported the bug on ARM/kirkwood when DEBUG_VM is enabled,
and this patch fixes the bug by adding test of '!PageSlab(miter->page)'
before calling flush_kernel_dcache_page().Signed-off-by: Ming Lei
Reported-by: Aaro Koskinen
Tested-by: Simon Baatz
Cc: Russell King - ARM Linux
Cc: Will Deacon
Cc: Aaro Koskinen
Acked-by: Catalin Marinas
Cc: FUJITA Tomonori
Cc: Tejun Heo
Cc: "James E.J. Bottomley"
Cc: Jens Axboe
Cc: [3.2+]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
29 Oct, 2013
1 commit
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Without the timer debugging, the delayed kobject release will just
result in undebuggable oopses if it triggers any latent bugs. That
doesn't actually help debugging at all.So make DEBUG_KOBJECT_RELEASE depend on DEBUG_OBJECTS_TIMERS to avoid
having people enable one without the other.Signed-off-by: Linus Torvalds
17 Oct, 2013
1 commit
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Export the interface to be used within modules.
Signed-off-by: Matias Bjorling
Acked-by: Tejun Heo
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Oct, 2013
1 commit
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Useful for locating buggy drivers on kernel oops.
It may add dozens of new lines to boot dmesg. DEBUG_KOBJECT_RELEASE is
hopefully only enabled in debug kernels (like maybe the Fedora rawhide
one, or at developers), so being a bit more verbose is likely ok.Acked-by: Russell King
Cc: Greg Kroah-Hartman
Signed-off-by: Fengguang Wu
Signed-off-by: Linus Torvalds
02 Oct, 2013
1 commit
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Pull networking changes from David Miller:
1) Multiply in netfilter IPVS can overflow when calculating destination
weight. From Simon Kirby.2) Use after free fixes in IPVS from Julian Anastasov.
3) SFC driver bug fixes from Daniel Pieczko.
4) Memory leak in pcan_usb_core failure paths, from Alexey Khoroshilov.
5) Locking and encapsulation fixes to serial line CAN driver, from
Andrew Naujoks.6) Duplex and VF handling fixes to bnx2x driver from Yaniv Rosner,
Eilon Greenstein, and Ariel Elior.7) In lapb, if no other packets are outstanding, T1 timeouts actually
stall things and no packet gets sent. Fix from Josselin Costanzi.8) ICMP redirects should not make it to the socket error queues, from
Duan Jiong.9) Fix bugs in skge DMA mapping error handling, from Nikulas Patocka.
10) Fix setting of VLAN priority field on via-rhine driver, from Roget
Luethi.11) Fix TX stalls and VLAN promisc programming in be2net driver from
Ajit Khaparde.12) Packet padding doesn't get handled correctly in new usbnet SG
support code, from Ming Lei.13) Fix races in netdevice teardown wrt. network namespace closing.
From Eric W. Biederman.14) Fix potential missed initialization of net_secret if not TCP
connections are openned. From Eric Dumazet.15) Cinterion PLXX product ID in qmi_wwan driver is wrong, from
Aleksander Morgado.16) skb_cow_head() can change skb->data and thus packet header pointers,
don't use stale ip_hdr reference in ip_tunnel code.17) Backend state transition handling fixes in xen-netback, from Paul
Durrant.18) Packet offset for AH protocol is handled wrong in flow dissector,
from Eric Dumazet.19) Taking down an fq packet scheduler instance can leave stale packets
in the queues, fix from Eric Dumazet.20) Fix performance regressions introduced by TCP Small Queues. From
Eric Dumazet.21) IPV6 GRE tunneling code calculates max_headroom incorrectly, from
Hannes Frederic Sowa.22) Multicast timer handlers in ipv4 and ipv6 can be the last and final
reference to the ipv4/ipv6 specific network device state, so use the
reference put that will check and release the object if the
reference hits zero. From Salam Noureddine.23) Fix memory corruption in ip_tunnel driver, and use skb_push()
instead of __skb_push() so that similar bugs are less hard to find.
From Steffen Klassert.24) Add forgotten hookup of rtnl_ops in SIT and ip6tnl drivers, from
Nicolas Dichtel.25) fq scheduler doesn't accurately rate limit in certain circumstances,
from Eric Dumazet.* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (103 commits)
pkt_sched: fq: rate limiting improvements
ip6tnl: allow to use rtnl ops on fb tunnel
sit: allow to use rtnl ops on fb tunnel
ip_tunnel: Remove double unregister of the fallback device
ip_tunnel_core: Change __skb_push back to skb_push
ip_tunnel: Add fallback tunnels to the hash lists
ip_tunnel: Fix a memory corruption in ip_tunnel_xmit
qlcnic: Fix SR-IOV configuration
ll_temac: Reset dma descriptors indexes on ndo_open
skbuff: size of hole is wrong in a comment
ipv6 mcast: use in6_dev_put in timer handlers instead of __in6_dev_put
ipv4 igmp: use in_dev_put in timer handlers instead of __in_dev_put
ethernet: moxa: fix incorrect placement of __initdata tag
ipv6: gre: correct calculation of max_headroom
powerpc/83xx: gianfar_ptp: select 1588 clock source through dts file
Revert "powerpc/83xx: gianfar_ptp: select 1588 clock source through dts file"
bonding: Fix broken promiscuity reference counting issue
tcp: TSQ can use a dynamic limit
dm9601: fix IFF_ALLMULTI handling
pkt_sched: fq: qdisc dismantle fixes
...
28 Sep, 2013
3 commits
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Make use of arch_mutex_cpu_relax() so architectures can override the
default cpu_relax() semantics.
This is especially useful for s390, where cpu_relax() means that we
yield() the current (virtual) cpu and therefore is very expensive,
and would contradict the whole purpose of the lockless cmpxchg loop.Signed-off-by: Heiko Carstens
-
In kobj_ns_current_may_mount the default should be to allow the mount.
The test is only for a single kobj_ns_type at a time, and unless there
is a reason to prevent it the mounting sysfs should be allowed.
Subsystems that are not registered can't have are not involved so can't
have a reason to prevent mounting sysfs.This is a bug-fix to commit 7dc5dbc879bd ("sysfs: Restrict mounting
sysfs") that came in via the userns tree during the 3.12 merge window.Reported-and-tested-by: James Hogan
Signed-off-by: "Eric W. Biederman"
Signed-off-by: Linus Torvalds -
The 64-bit cmpxchg operation on the lockref is ordered by virtue of
hazarding between the cmpxchg operation and the reference count
manipulation. On weakly ordered memory architectures (such as ARM), it
can be of great benefit to omit the barrier instructions where they are
not needed.This patch moves the lockless lockref code over to a cmpxchg64_relaxed
operation, which doesn't provide barrier semantics. If the operation
isn't defined, we simply #define it as the usual 64-bit cmpxchg macro.Cc: Waiman Long
Signed-off-by: Will Deacon
Signed-off-by: Linus Torvalds
21 Sep, 2013
2 commits
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To be able to use the hex ascii functions in case sensitive environments
the array hex_asc_upper[] and the needed functions for hex_byte_pack_upper()
are introduced.Signed-off-by: Andre Naujoks
Signed-off-by: David S. Miller -
The cmpxchg() function tends not to support 64-bit arguments on 32-bit
architectures. This could be either due to use of unsigned long
arguments (like on ARM) or lack of instruction support (cmpxchgq on
x86). However, these architectures may implement a specific cmpxchg64()
function to provide 64-bit cmpxchg support instead.Since the lockref code requires a 64-bit cmpxchg and relies on the
architecture selecting ARCH_USE_CMPXCHG_LOCKREF, move to using cmpxchg64
instead of cmpxchg and allow 32-bit architectures to make use of the
lockless lockref implementation.Cc: Waiman Long
Signed-off-by: Will Deacon
Signed-off-by: Linus Torvalds
13 Sep, 2013
4 commits
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Pull generic hardirq option removal from Martin Schwidefsky:
"All architectures now use generic hardirqs, s390 has been last to
switch.With that the code under !CONFIG_GENERIC_HARDIRQS and the related
HAVE_GENERIC_HARDIRQS and GENERIC_HARDIRQS config options can be
removed. Yay!"* 'genirq' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
Remove GENERIC_HARDIRQ config option -
Pull crypto fixes from Herbert Xu:
"This fixes a 7+ year race condition in the crypto API that causes
sporadic crashes when multiple threads load the same algorithm.It also fixes the crct10dif algorithm again to prevent boot failures
on systems where the initramfs tool ignores module softdeps"* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: crct10dif - Add fallback for broken initrds
crypto: api - Fix race condition in larval lookup -
After the last architecture switched to generic hard irqs the config
options HAVE_GENERIC_HARDIRQS & GENERIC_HARDIRQS and the related code
for !CONFIG_GENERIC_HARDIRQS can be removed.Signed-off-by: Martin Schwidefsky
-
Pull SCSI target updates from Nicholas Bellinger:
"Lots of activity again this round for I/O performance optimizations
(per-cpu IDA pre-allocation for vhost + iscsi/target), and the
addition of new fabric independent features to target-core
(COMPARE_AND_WRITE + EXTENDED_COPY).The main highlights include:
- Support for iscsi-target login multiplexing across individual
network portals
- Generic Per-cpu IDA logic (kent + akpm + clameter)
- Conversion of vhost to use per-cpu IDA pre-allocation for
descriptors, SGLs and userspace page pointer list
- Conversion of iscsi-target + iser-target to use per-cpu IDA
pre-allocation for descriptors
- Add support for generic COMPARE_AND_WRITE (AtomicTestandSet)
emulation for virtual backend drivers
- Add support for generic EXTENDED_COPY (CopyOffload) emulation for
virtual backend drivers.
- Add support for fast memory registration mode to iser-target (Vu)The patches to add COMPARE_AND_WRITE and EXTENDED_COPY support are of
particular significance, which make us the first and only open source
target to support the full set of VAAI primitives.Currently Linux clients are lacking upstream support to actually
utilize these primitives. However, with server side support now in
place for folks like MKP + ZAB working on the client, this logic once
reserved for the highest end of storage arrays, can now be run in VMs
on their laptops"* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (50 commits)
target/iscsi: Bump versions to v4.1.0
target: Update copyright ownership/year information to 2013
iscsi-target: Bump default TCP listen backlog to 256
target: Fix >= v3.9+ regression in PR APTPL + ALUA metadata write-out
iscsi-target; Bump default CmdSN Depth to 64
iscsi-target: Remove unnecessary wait_for_completion in iscsi_get_thread_set
iscsi-target: Add thread_set->ts_activate_sem + use common deallocate
iscsi-target: Fix race with thread_pre_handler flush_signals + ISCSI_THREAD_SET_DIE
target: remove unused including
iser-target: introduce fast memory registration mode (FRWR)
iser-target: generalize rdma memory registration and cleanup
iser-target: move rdma wr processing to a shared function
target: Enable global EXTENDED_COPY setup/release
target: Add Third Party Copy (3PC) bit in INQUIRY response
target: Enable EXTENDED_COPY setup in spc_parse_cdb
target: Add support for EXTENDED_COPY copy offload emulation
target: Avoid non-existent tg_pt_gp_mem in target_alua_state_check
target: Add global device list for EXTENDED_COPY
target: Make helpers non static for EXTENDED_COPY command setup
target: Make spc_parse_naa_6h_vendor_specific non static
...
12 Sep, 2013
11 commits
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Unfortunately, even with a softdep some distros fail to include
the necessary modules in the initrd. Therefore this patch adds
a fallback path to restore existing behaviour where we cannot
load the new crypto crct10dif algorithm.In order to do this, the underlying crct10dif has been split out
from the crypto implementation so that it can be used on the
fallback path.Signed-off-by: Herbert Xu
-
LZ4 compression and decompression functions require different in
signedness input/output parameters: unsigned char for compression and
signed char for decompression.Change decompression API to require "(const) unsigned char *".
Signed-off-by: Sergey Senozhatsky
Cc: Kyungsik Lee
Cc: Geert Uytterhoeven
Cc: Yann Collet
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
With users of radix_tree_preload() run from interrupt (block/blk-ioc.c is
one such possible user), the following race can happen:radix_tree_preload()
...
radix_tree_insert()
radix_tree_node_alloc()
if (rtp->nr) {
ret = rtp->nodes[rtp->nr - 1];...
radix_tree_preload()
...
radix_tree_insert()
radix_tree_node_alloc()
if (rtp->nr) {
ret = rtp->nodes[rtp->nr - 1];And we give out one radix tree node twice. That clearly results in radix
tree corruption with different results (usually OOPS) depending on which
two users of radix tree race.We fix the problem by making radix_tree_node_alloc() always allocate fresh
radix tree nodes when in interrupt. Using preloading when in interrupt
doesn't make sense since all the allocations have to be atomic anyway and
we cannot steal nodes from process-context users because some users rely
on radix_tree_insert() succeeding after radix_tree_preload().
in_interrupt() check is somewhat ugly but we cannot simply key off passed
gfp_mask as that is acquired from root_gfp_mask() and thus the same for
all preload users.Another part of the fix is to avoid node preallocation in
radix_tree_preload() when passed gfp_mask doesn't allow waiting. Again,
preallocation in such case doesn't make sense and when preallocation would
happen in interrupt we could possibly leak some allocated nodes. However,
some users of radix_tree_preload() require following radix_tree_insert()
to succeed. To avoid unexpected effects for these users,
radix_tree_preload() only warns if passed gfp mask doesn't allow waiting
and we provide a new function radix_tree_maybe_preload() for those users
which get different gfp mask from different call sites and which are
prepared to handle radix_tree_insert() failure.Signed-off-by: Jan Kara
Cc: Jens Axboe
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
No reason require rbtree test code to be a module, allow it to be builtin
(streamlines my development process)Signed-off-by: Cody P Schafer
Reviewed-by: Seth Jennings
Cc: David Woodhouse
Cc: Rik van Riel
Cc: Michel Lespinasse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Just check that we examine all nodes in the tree for the postorder
iteration.Signed-off-by: Cody P Schafer
Reviewed-by: Seth Jennings
Cc: David Woodhouse
Cc: Rik van Riel
Cc: Michel Lespinasse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Postorder iteration yields all of a node's children prior to yielding the
node itself, and this particular implementation also avoids examining the
leaf links in a node after that node has been yielded.In what I expect will be its most common usage, postorder iteration allows
the deletion of every node in an rbtree without modifying the rbtree nodes
(no _requirement_ that they be nulled) while avoiding referencing child
nodes after they have been "deleted" (most commonly, freed).I have only updated zswap to use this functionality at this point, but
numerous bits of code (most notably in the filesystem drivers) use a hand
rolled postorder iteration that NULLs child links as it traverses the
tree. Each of those instances could be replaced with this common
implementation.1 & 2 add rbtree postorder iteration functions.
3 adds testing of the iteration to the rbtree runtime tests
4 allows building the rbtree runtime tests as builtins
5 updates zswap.This patch:
Add postorder iteration functions for rbtree. These are useful for safely
freeing an entire rbtree without modifying the tree at all.Signed-off-by: Cody P Schafer
Reviewed-by: Seth Jennings
Cc: David Woodhouse
Cc: Rik van Riel
Cc: Michel Lespinasse
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When decompressing into memory, the output buffer length is set to some
arbitrarily high value (0x7fffffff) to indicate the output is, virtually,
unlimited in size.The problem with this is that some platforms have their physical memory at
high physical addresses (0x80000000 or more), and that the output buffer
address and its "unlimited" length cannot be added without overflowing.
An example of this can be found in inflate_fast():/* next_out is the output buffer address */
out = strm->next_out - OFF;
/* avail_out is the output buffer size. end will overflow if the output
* address is >= 0x80000104 */
end = out + (strm->avail_out - 257);This has huge consequences on the performance of kernel decompression,
since the following exit condition of inflate_fast() will be always true:} while (in < last && out < end);
Indeed, "end" has overflowed and is now always lower than "out". As a
result, inflate_fast() will return after processing one single byte of
input data, and will thus need to be called an unreasonably high number of
times. This probably went unnoticed because kernel decompression is fast
enough even with this issue.Nonetheless, adjusting the output buffer length in such a way that the
above pointer arithmetic never overflows results in a kernel decompression
that is about 3 times faster on affected machines.Signed-off-by: Alexandre Courbot
Tested-by: Jon Medhurst
Cc: Stephen Warren
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Gu Zheng
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
The documentation mentions a "name" parameter, which does not exist. This
commit removes such mention from the function documentation.Signed-off-by: Emilio López
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Use the helper function instead of __GFP_ZERO.
Signed-off-by: Joe Perches
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In struct gen_pool_chunk, end_addr means the end address of memory chunk
(inclusive), but in the implementation it is treated as address + size of
memory chunk (exclusive), so it points to the address plus one instead of
correct ending address.The ending address of memory chunk plus one will cause overflow on the
memory chunk including the last address of memory map, e.g. when starting
address is 0xFFF00000 and size is 0x100000 on 32bit machine, ending
address will be 0x100000000.Use correct ending address like starting address + size - 1.
[akpm@linux-foundation.org: add comment to struct gen_pool_chunk:end_addr]
Signed-off-by: Joonyoung Shim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
11 Sep, 2013
2 commits
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Pull device-mapper updates from Mike Snitzer:
"Add the ability to collect I/O statistics on user-defined regions of a
device-mapper device. This dm-stats code required the reintroduction
of a div64_u64_rem() helper, but as a separate method that doesn't
slow down div64_u64() -- especially on 32-bit systems.Allow the error target to replace request-based DM devices (e.g.
multipath) in addition to bio-based DM devices.Various other small code fixes and improvements to thin-provisioning,
DM cache and the DM ioctl interface"* tag 'dm-3.12-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm stripe: silence a couple sparse warnings
dm: add statistics support
dm thin: always return -ENOSPC if no_free_space is set
dm ioctl: cleanup error handling in table_load
dm ioctl: increase granularity of type_lock when loading table
dm ioctl: prevent rename to empty name or uuid
dm thin: set pool read-only if breaking_sharing fails block allocation
dm thin: prefix pool error messages with pool device name
dm: allow error target to replace bio-based and request-based targets
math64: New separate div64_u64_rem helper
dm space map: optimise sm_ll_dec and sm_ll_inc
dm btree: prefetch child nodes when walking tree for a dm_btree_del
dm btree: use pop_frame in dm_btree_del to cleanup code
dm cache: eliminate holes in cache structure
dm cache: fix stacking of geometry limits
dm thin: fix stacking of geometry limits
dm thin: add data block size limits to Documentation
dm cache: add data block size limits to code and Documentation
dm cache: document metadata device is exclussive to a cache
dm: stop using WQ_NON_REENTRANT -
Pull md update from Neil Brown:
"Headline item is multithreading for RAID5 so that more IO/sec can be
supported on fast (SSD) devices. Also TILE-Gx SIMD suppor for RAID6
calculations and an assortment of bug fixes"* tag 'md/3.12' of git://neil.brown.name/md:
raid5: only wakeup necessary threads
md/raid5: flush out all pending requests before proceeding with reshape.
md/raid5: use seqcount to protect access to shape in make_request.
raid5: sysfs entry to control worker thread number
raid5: offload stripe handle to workqueue
raid5: fix stripe release order
raid5: make release_stripe lockless
md: avoid deadlock when dirty buffers during md_stop.
md: Don't test all of mddev->flags at once.
md: Fix apparent cut-and-paste error in super_90_validate
raid6/test: replace echo -e with printf
RAID: add tilegx SIMD implementation of raid6
md: fix safe_mode buglet.
md: don't call md_allow_write in get_bitmap_file.
10 Sep, 2013
2 commits
-
Percpu frontend for allocating ids. With percpu allocation (that works),
it's impossible to guarantee it will always be possible to allocate all
nr_tags - typically, some will be stuck on a remote percpu freelist
where the current job can't get to them.We do guarantee that it will always be possible to allocate at least
(nr_tags / 2) tags - this is done by keeping track of which and how many
cpus have tags on their percpu freelists. On allocation failure if
enough cpus have tags that there could potentially be (nr_tags / 2) tags
stuck on remote percpu freelists, we then pick a remote cpu at random to
steal from.Note that there's no cpu hotplug notifier - we don't care, because
steal_tags() will eventually get the down cpu's tags. We _could_ satisfy
more allocations if we had a notifier - but we'll still meet our
guarantees and it's absolutely not a correctness issue, so I don't think
it's worth the extra code.From akpm:
"It looks OK to me (that's as close as I get to an ack :))
v6 changes:
- Add #include to include/linux/percpu_ida.h to
make alpha/arc builds happy (Fengguang)
- Move second (cpu >= nr_cpu_ids) check inside of first check scope
in steal_tags() (akpm + nab)v5 changes:
- Change percpu_ida->cpus_have_tags to cpumask_t (kmo + akpm)
- Add comment for percpu_ida_cpu->lock + ->nr_free (kmo + akpm)
- Convert steal_tags() to use cpumask_weight() + cpumask_next() +
cpumask_first() + cpumask_clear_cpu() (kmo + akpm)
- Add comment for alloc_global_tags() (kmo + akpm)
- Convert percpu_ida_alloc() to use cpumask_set_cpu() (kmo + akpm)
- Convert percpu_ida_free() to use cpumask_set_cpu() (kmo + akpm)
- Drop percpu_ida->cpus_have_tags allocation in percpu_ida_init()
(kmo + akpm)
- Drop percpu_ida->cpus_have_tags kfree in percpu_ida_destroy()
(kmo + akpm)
- Add comment for percpu_ida_alloc @ gfp (kmo + akpm)
- Move to percpu_ida.c + percpu_ida.h (kmo + akpm + nab)v4 changes:
- Fix tags.c reference in percpu_ida_init (akpm)
Signed-off-by: Kent Overstreet
Cc: Tejun Heo
Cc: Oleg Nesterov
Cc: Christoph Lameter
Cc: Ingo Molnar
Cc: Andi Kleen
Cc: Jens Axboe
Cc: "Nicholas A. Bellinger"
Signed-off-by: Nicholas Bellinger -
Pull ARC changes from Vineet Gupta:
- ARC MM changes:
- preparation for MMUv4 (accomodate new PTE bits, new cmds)
- Rework the ASID allocation algorithm to remove asid-mm reverse map
- Boilerplate code consolidation in Exception Handlers
- Disable FRAME_POINTER for ARC
- Unaligned Access Emulation for Big-Endian from Noam
- Bunch of fixes (udelay, missing accessors) from Mischa* tag 'arc-v3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc:
ARC: fix new Section mismatches in build (post __cpuinit cleanup)
Kconfig.debug: Add FRAME_POINTER anti-dependency for ARC
ARC: Fix __udelay calculation
ARC: remove console_verbose() from setup_arch()
ARC: Add read*_relaxed to asm/io.h
ARC: Handle un-aligned user space access in BE.
ARC: [ASID] Track ASID allocation cycles/generations
ARC: [ASID] activate_mm() == switch_mm()
ARC: [ASID] get_new_mmu_context() to conditionally allocate new ASID
ARC: [ASID] Refactor the TLB paranoid debug code
ARC: [ASID] Remove legacy/unused debug code
ARC: No need to flush the TLB in early boot
ARC: MMUv4 preps/3 - Abstract out TLB Insert/Delete
ARC: MMUv4 preps/2 - Reshuffle PTE bits
ARC: MMUv4 preps/1 - Fold PTE K/U access flags
ARC: Code cosmetics (Nothing semantical)
ARC: Entry Handler tweaks: Optimize away redundant IRQ_DISABLE_SAVE
ARC: Exception Handlers Code consolidation
ARC: Add some .gitignore entries
08 Sep, 2013
4 commits
-
The only actual current lockref user (dcache) uses zero reference counts
even for perfectly live dentries, because it's a cache: there may not be
any users, but that doesn't mean that we want to throw away the dentry.At the same time, the dentry cache does have a notion of a truly "dead"
dentry that we must not even increment the reference count of, because
we have pruned it and it is not valid.Currently that distinction is not visible in the lockref itself, and the
dentry cache validation uses "lockref_get_or_lock()" to either get a new
reference to a dentry that already had existing references (and thus
cannot be dead), or get the dentry lock so that we can then verify the
dentry and increment the reference count under the lock if that
verification was successful.That's all somewhat complicated.
This adds the concept of being "dead" to the lockref itself, by simply
using a count that is negative. This allows a usage scenario where we
can increment the refcount of a dentry without having to validate it,
and pushing the special "we killed it" case into the lockref code.The dentry code itself doesn't actually use this yet, and it's probably
too late in the merge window to do that code (the dentry_kill() code
with its "should I decrement the count" logic really is pretty complex
code), but let's introduce the concept at the lockref level now.Signed-off-by: Linus Torvalds
-
The code got rewritten, but the comments got copied as-is from older
versions, and as a result the argument name in the comment didn't
actually match the code any more.Signed-off-by: Linus Torvalds
-
Pull namespace changes from Eric Biederman:
"This is an assorted mishmash of small cleanups, enhancements and bug
fixes.The major theme is user namespace mount restrictions. nsown_capable
is killed as it encourages not thinking about details that need to be
considered. A very hard to hit pid namespace exiting bug was finally
tracked and fixed. A couple of cleanups to the basic namespace
infrastructure.Finally there is an enhancement that makes per user namespace
capabilities usable as capabilities, and an enhancement that allows
the per userns root to nice other processes in the user namespace"* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
userns: Kill nsown_capable it makes the wrong thing easy
capabilities: allow nice if we are privileged
pidns: Don't have unshare(CLONE_NEWPID) imply CLONE_THREAD
userns: Allow PR_CAPBSET_DROP in a user namespace.
namespaces: Simplify copy_namespaces so it is clear what is going on.
pidns: Fix hang in zap_pid_ns_processes by sending a potentially extra wakeup
sysfs: Restrict mounting sysfs
userns: Better restrictions on when proc and sysfs can be mounted
vfs: Don't copy mount bind mounts of /proc//ns/mnt between namespaces
kernel/nsproxy.c: Improving a snippet of code.
proc: Restrict mounting the proc filesystem
vfs: Lock in place mounts from more privileged users -
Pull crypto update from Herbert Xu:
"Here is the crypto update for 3.12:- Added MODULE_SOFTDEP to allow pre-loading of modules.
- Reinstated crct10dif driver using the module softdep feature.
- Allow via rng driver to be auto-loaded.- Split large input data when necessary in nx.
- Handle zero length messages correctly for GCM/XCBC in nx.
- Handle SHA-2 chunks bigger than block size properly in nx.- Handle unaligned lengths in omap-aes.
- Added SHA384/SHA512 to omap-sham.
- Added OMAP5/AM43XX SHAM support.
- Added OMAP4 TRNG support.- Misc fixes"
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (66 commits)
Reinstate "crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework"
hwrng: via - Add MODULE_DEVICE_TABLE
crypto: fcrypt - Fix bitoperation for compilation with clang
crypto: nx - fix SHA-2 for chunks bigger than block size
crypto: nx - fix GCM for zero length messages
crypto: nx - fix XCBC for zero length messages
crypto: nx - fix limits to sg lists for AES-CCM
crypto: nx - fix limits to sg lists for AES-XCBC
crypto: nx - fix limits to sg lists for AES-GCM
crypto: nx - fix limits to sg lists for AES-CTR
crypto: nx - fix limits to sg lists for AES-CBC
crypto: nx - fix limits to sg lists for AES-ECB
crypto: nx - add offset to nx_build_sg_lists()
padata - Register hotcpu notifier after initialization
padata - share code between CPU_ONLINE and CPU_DOWN_FAILED, same to CPU_DOWN_PREPARE and CPU_UP_CANCELED
hwrng: omap - reorder OMAP TRNG driver code
crypto: omap-sham - correct dma burst size
crypto: omap-sham - Enable Polling mode if DMA fails
crypto: tegra-aes - bitwise vs logical and
crypto: sahara - checking the wrong variable
...
07 Sep, 2013
1 commit
-
This patch reinstates commits
67822649d7305caf3dd50ed46c27b99c94eff996
39761214eefc6b070f29402aa1165f24d789b3f7
0b95a7f85718adcbba36407ef88bba0a7379ed03
31d939625a9a20b1badd2d4e6bf6fd39fa523405
2d31e518a42828df7877bca23a958627d60408bcNow that module softdeps are in the kernel we can use that to resolve
the boot issue which cause the revert.Signed-off-by: Herbert Xu
06 Sep, 2013
1 commit
-
Pull ARM updates from Russell King:
"This set includes adding support for Neon acceleration of RAID6 XOR
code from Ard Biesheuvel, cache flushing and barrier updates from Will
Deacon, and a cleanup to the ARM debug code which reduces the amount
of code by about 500 lines.A few other cleanups, such as constifying the machine descriptors
which already shouldn't be written to, cleaning up the printing of the
L2 cache size"* 'for-linus' of git://git.linaro.org/people/rmk/linux-arm: (55 commits)
ARM: 7826/1: debug: support debug ll on hisilicon soc
ARM: 7830/1: delay: don't bother reporting bogomips in /proc/cpuinfo
ARM: 7829/1: Add ".text.unlikely" and ".text.hot" to arm unwind tables
ARM: 7828/1: ARMv7-M: implement restart routine common to all v7-M machines
ARM: 7827/1: highbank: fix debug uart virtual address for LPAE
ARM: 7823/1: errata: workaround Cortex-A15 erratum 773022
ARM: 7806/1: allow DEBUG_UNCOMPRESS for Tegra
ARM: 7793/1: debug: use generic option for ep93xx PL10x debug port
ARM: debug: move SPEAr debug to generic PL01x code
ARM: debug: move davinci debug to generic 8250 code
ARM: debug: move keystone debug to generic 8250 code
ARM: debug: remove DEBUG_ROCKCHIP_UART
ARM: debug: provide generic option choices for 8250 and PL01x ports
ARM: debug: move PL01X debug include into arch/arm/include/debug/
ARM: debug: provide PL01x debug uart phys/virt address configuration options
ARM: debug: add support for word accesses to debug/8250.S
ARM: debug: move 8250 debug include into arch/arm/include/debug/
ARM: debug: provide 8250 debug uart phys/virt address configuration options
ARM: debug: provide 8250 debug uart register shift configuration option
ARM: debug: provide 8250 debug uart flow control configuration option
...
05 Sep, 2013
3 commits
-
Pull vfs pile 1 from Al Viro:
"Unfortunately, this merge window it'll have a be a lot of small piles -
my fault, actually, for not keeping #for-next in anything that would
resemble a sane shape ;-/This pile: assorted fixes (the first 3 are -stable fodder, IMO) and
cleanups + %pd/%pD formats (dentry/file pathname, up to 4 last
components) + several long-standing patches from various folks.There definitely will be a lot more (starting with Miklos'
check_submount_and_drop() series)"* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (26 commits)
direct-io: Handle O_(D)SYNC AIO
direct-io: Implement generic deferred AIO completions
add formats for dentry/file pathnames
kvm eventfd: switch to fdget
powerpc kvm: use fdget
switch fchmod() to fdget
switch epoll_ctl() to fdget
switch copy_module_from_fd() to fdget
git simplify nilfs check for busy subtree
ibmasmfs: don't bother passing superblock when not needed
don't pass superblock to hypfs_{mkdir,create*}
don't pass superblock to hypfs_diag_create_files
don't pass superblock to hypfs_vm_create_files()
oprofile: get rid of pointless forward declarations of struct super_block
oprofilefs_create_...() do not need superblock argument
oprofilefs_mkdir() doesn't need superblock argument
don't bother with passing superblock to oprofile_create_stats_files()
oprofile: don't bother with passing superblock to ->create_files()
don't bother passing sb to oprofile_create_files()
coh901318: don't open-code simple_read_from_buffer()
... -
Frame pointer on ARC doesn't serve the conventional purpose of stack
unwinding due to the typical way ABI designates it's usage.
Thus it's explicit usage on ARC is discouraged (gcc is free to use it,
for some tricky stack frames even if -fomit-frame-pointer).Hence no point enabling it for ARC.
References: http://www.spinics.net/lists/kernel/msg1593937.html
Signed-off-by: Vineet Gupta
Cc: Dave Hansen
Cc: Andrew Morton
Cc: "Paul E. McKenney"
Cc: Catalin Marinas
Cc: Michel Lespinasse
Cc: linux-kernel@vger.kernel.org
